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Zapping water with electricity could save your life.
给水通电能救命。
Not something you thought we'd ever say?
以为我们绝不可能说出这样的话？
We're shocked, too.
其实我们也很震惊。
By introducing an electric current into lead pipes filled with a harmless phosphate solution,
通过给灌满无毒的磷酸盐溶液的铅管中引入电流，
researchers at UC Berkeley were able to rapidly form a protective coating around corroded lead pipes,
加州大学伯克利分校的研究人员迅速给腐蚀的铅管镀上了一层保护层，
reducing leaching of this toxic element by roughly 99%.
将这种有毒元素的浸出率降低了将近99%。
Lead exposure is a huge public health issue, according to The World Health Organization.
据世界卫生组织透露，铅暴露构成了一个巨大的公共健康问题。
Paint and dust laced with lead are the most common sources of exposure,
尽管油漆和含铅灰尘是最常见的暴露形式，
but contaminated water is another big issue.
但水污染引起的铅暴露问题也很严重。
In the U.S. alone, over 5,000 water systems violate the EPA's Safe Drinking Water Act, placing an estimated 18 million people at risk.
仅美国就有5000多个供水系统违反了美国环保署的《安全饮用水法》，预计有1800万人因此陷入了铅暴露的危险之中。
And lead poisoning is no joke.
而且，铅中毒可不是闹着玩儿的。
This chemical element (Pb) can accumulate in our body over time,
这种化学元素(Pb)能够随时间在我们体内堆积，
leading to kidney damage, reduced IQ, increased risk of cancer, stroke, and even death.
引发肾脏受损、智商下降等问题，还会加大癌症、中风甚至死亡等风险。
That's all thanks to lead's sneaky ability to mimic and inhibit calcium, break through the blood-brain barrier,
而这一切都是因为铅能够非常狡猾地模拟继而抑制钙这种元素，还能突破血脑屏障，
and result in the misfiring of neural signals, impairing our ability to learn and develop.
触发错误的神经信号，损害我们学习能力和发育能力。
Evidence suggests that ancient Romans knew their lead pipes were poisonous,
有证据表明古罗马人就已经知道他们的铅管有毒了，
but lead's dangers weren't widely re-discovered until the period of industrialization in the 19th century,
但到了19世纪工业化时期铅中毒的报道开始增多时，
when reports of lead poisoning began to pick up.
人们才广泛意识到这种金属的危险性。
Decades of subsequent scientific investigation and their damming findings
随后几十年的科学研究及这些研究的确凿发现
eventually prompted many governments to distance themselves from sources of lead, like gasoline additives, paint, and piping material,
终于促使许多政府开始远离汽油添加剂、油漆和管材之类的铅源，
which was favored as a durable and long-lasting material well into the 20th century.
因为作为一种经久耐用的材料，一直到20世纪开始很久以后，铅都深受着大家的欢迎。
But it takes time to redo the plumbing of entire cities,
问题是，要给整座城市重新铺设管道需要时间，
as was made painfully clear when taps in Flint, Michigan began dispensing lead-contaminated water to residents in 2014.
2014年，密歇根州弗林特市的自来水龙头开始流出被铅污染的水时，这一问题明显到令人揪心。
One sample even had lead levels reaching 13,200 parts per billion!
其中一个样本的铅含量甚至达到了13200ppm！
So. we're stuck with all this lead-laden water.
看来，这些含铅的水我们是摆脱不了了。
Now what?
那怎么办呢？
Water doesn't contain much lead on its own, but it can be corrosive.
水本身的含铅量并不高，但它也能变得具有腐蚀性。
Once in contact with lead pipes, it can breakdown the metal and cause leaching.
一旦与铅管接触，水就会分解这种金属并引发铅泄露。
To prevent this, inorganic phosphates are commonly added to public water supplies,
为了防止这种情况，人们通常会往公共水源里添加无机磷酸盐，
where they react with positively charged lead ions to form a protective, insoluble mineral scale on the inside of pipes.
磷酸盐与带正电荷的铅离子发生反应后，会在管道内部形成一层能够起到保护作用的不溶性矿物垢。
But without maintaining tight control of the chemistry, that coating is quickly eaten away.
但如果不严格控制这一化学反应，这种涂层很快就会被腐蚀掉。
To fix a water supply that's turned toxic, pipe replacement is by far the best solution, but it's extremely costly and slow.
要修复有毒的供水系统，更换水管是目前为止最好的办法，但这种办法成本极高，而且速度很慢。
Case in point: it took two years after Flint's water crisis erupted for the city's roughly 170 million dollar pipe replacement program to break ground.
举个例子：弗林特的自来水危机爆发后，该市花了两年时间，耗资约1.7亿美元的管道更换项目才得以破土动工。
And as of 2019, roughly 2,500 lines still need replacement.
到今年为止，该市都大约还有2500条管道需要更换。
So is there a better way to zap the situation?
那么，还有没有更好的办法能解决这个问题呢？
In our work, we ask the question,
在工作中，我们会问这样一个问题，
what can we do to rapidly stop a leaching lead pipe
我们怎样才能迅速停止铅管的渗漏，
so that the drinking water that passes through it will become safe all over again?
让流经这些管道的饮用水重新变得安全？”
The team specializes in drinking water treatment using electro-chemistry,
该团队的专长是采用电化学方法处理饮用水，
which is the science of looking at how electricity interacts with materials.
电化学就是研究电与各种材料发生作用的科学。
It starts by introducing a threaded wire down the inside of a lead pipe into a tank of water filled with phosphates, then switching on an electric circuit.
首先，将一根导线穿过铅管内部，再插入装满磷酸盐溶液的水箱，然后接通电路。
At first, the voltage causes lead ions to leach into the water,
起初，电压会导致铅离子开始往水中渗漏，
but as these ions react with the phosphates, they begin to form insoluble lead phosphate.
但这些离子与水箱里的磷酸盐反应后生成不溶性磷酸铅。
Searching for somewhere to deposit, these minerals begin to settle on the lead pipe itself.
这些矿物质会找地方沉着，继而就会开始重新附着到铅管上。
As the lead phosphate lines the inside of the lead pipe for a given voltage,
在给定电压下，磷酸铅会沿着铅管内部沉着，
less and less current can flow because the lead pipe becomes non-conducting.
铅管的导电性会变差，电流就会越来越小。
that's how we know that our process is working.
我们就是这样知道这个方法在起作用的。
We can reduce the leaching of lead from those pipes by a factor of about 150.
我们可以将这些管道中铅的浸出率降低到原来的1/150左右。
We have not tested it yet in the field, but we have a solution that works.
我们还没有进行实地测验，但我们的方法是管用的。
Their preliminary results found that once a charge is introduced,
他们的初步实验结果发现，一旦引入电荷，
a mineral barrier can accumulate on the pipe wall in less than 2 hours,
不到2小时就可在管壁上形成一层矿物屏障，
effectively decreasing lead leaching by 99%.
将铅的浸出率有效降低99%。
Any part of the lead pipe that's left uncoated, the current self-tunes to go where it needs to go.
任何没有被矿物层覆盖到的地方，电流都会自动前往它该去的地方。
As for cost, it's cheap.
这种办法的成本也很低廉。
So there is also a sense of public responsibility in fixing the problem.
解决这个问题也是一种社会责任吧。
Replacing a pipe costs about 100 dollars a foot if you fold in all the costs.
如果把所有的费用都算进去，换一根管子，造价就高达每英尺100美元左右。
Our goal is to bring that cost down to, maybe, three dollars a foot.
我们的目标是把成本降到差不多每英尺3美元。
Water chemistry varies by a lot.
水的化学性质会受很多因素的影响。
So we haven't explored all that space of unknowns to say "oh yeah, we got the silver bullet.
我们还没有探索完所有未知的空间，可以做到说“啊，是的，我们想到了一个绝妙的办法。
We need to test it out, but we are ready to do that very soon we think.
我们还需要进一步的测试，但我感觉已经快了。
If all goes well, the team plans to try their technique in nearby schools as early as this year.
如果一切顺利，该研究小组计划最早于今年以附近的学校为试点来实地测试他们的技术。
Once refined, this technology could act as a vital stopgap
一旦完善，这项技术便可以作为重要的权宜之计，
until communities are able to replace lead pipes, as that ultimately remains the best solution.
直到各个社区有能力更换那些铅管为止，因为说到底，更换才是最好的办法。
And maybe a 5-star filter for your water tap.
也许你的自来水龙头还需要一个5星级的过滤器。
Are you excited about this research to stop this toxin from polluting our tap?
你觉得，看过这项阻止毒素污染我们的自来水的研究，你激动吗？
Let us know in the comments below, and don't forget to subscribe for more Seeker.
快在下方的评论中告诉我们吧，别忘了订阅观看更多节目噢。
I'll see you next time.
我们下期再见啦。
